Despite the worldwide economic impact of, and welfare issues associated with, infectious bovine abortifacients, as well as potential zoonotic threats to human health, accurate diagnosis of the causes of abortion is uncommon... Although Chlamydophila abortus is a known etiologic agent of ruminant abortion, several novel species of Chlamydia-like organisms have recently emerged as putative ruminant abortifacients... Serologic, bacteriologic, and histopathologic examination of fetal tissues identified no other infectious abortifacient agents in the Chlamydiales-positive samples... Sequence information was successfully obtained for 15 of these 22 samples with forward and reverse primers; sequences ranged from 140 bp to 194 bp (European Molecular Biology Laboratory/GenBank accession nos... GQ919016–GQ919030)... These 15 short sequences were carefully aligned to a representative set of 22 similar Chlamydiales 16S rDNA sequences, identified by a BLAST (www.ncbi.nlm.nih.gov/BLAST) similarity search of the European Molecular Biology Laboratory/GenBank database, plus alignment of an outgroup of 7 non-Chlamydiales sequences... Two of these sequence clusters represented 10 and 5 of the samples, whereas no samples were represented in the cluster containing the Chlamydiaceae, which includes C. abortus... Most (10/15) sequences were found in the cluster containing the Parachlamydiaceae... This finding agrees with those of the aborted bovine placenta studies in Switzerland and provides further evidence that Parachlamydia-like species may play a substantial role in bovine abortion in mainland Europe and the United Kingdom... Given the zoonotic potential and the economic and welfare impacts of bovine abortion on the agricultural sector, further studies are required to understand the incidence and pathogenic roles of these organisms in both humans and animals... These studies should include broader molecular epidemiologic studies, as well as detailed histologic/immunohistochemical investigations and organism recovery through culture of infected placental and fetal tissues.

Mentions:
Despite the short sequence length of the 15 samples, the tree was well resolved with the Chlamydiales sequences and formed 3 clusters (Chlamydiaceae, Rhabdochlamydiaceae/Simkaniaceae, and Parachlamydiaceae/Waddliaceae/Criblamydiaceae) (Figure). Two of these sequence clusters represented 10 and 5 of the samples, whereas no samples were represented in the cluster containing the Chlamydiaceae, which includes C. abortus. Most (10/15) sequences were found in the cluster containing the Parachlamydiaceae. This finding agrees with those of the aborted bovine placenta studies in Switzerland (3,4) and provides further evidence that Parachlamydia-like species may play a substantial role in bovine abortion in mainland Europe and the United Kingdom. Four of the remaining 5 samples clustered with members of the family Rhabdochlamydiaceae; the fifth sequence (CLBUK3), although present in the same Rhabdochlamydiaceae/Simkaniaceae cluster, appeared to be more distinct from other family members.

Mentions:
Despite the short sequence length of the 15 samples, the tree was well resolved with the Chlamydiales sequences and formed 3 clusters (Chlamydiaceae, Rhabdochlamydiaceae/Simkaniaceae, and Parachlamydiaceae/Waddliaceae/Criblamydiaceae) (Figure). Two of these sequence clusters represented 10 and 5 of the samples, whereas no samples were represented in the cluster containing the Chlamydiaceae, which includes C. abortus. Most (10/15) sequences were found in the cluster containing the Parachlamydiaceae. This finding agrees with those of the aborted bovine placenta studies in Switzerland (3,4) and provides further evidence that Parachlamydia-like species may play a substantial role in bovine abortion in mainland Europe and the United Kingdom. Four of the remaining 5 samples clustered with members of the family Rhabdochlamydiaceae; the fifth sequence (CLBUK3), although present in the same Rhabdochlamydiaceae/Simkaniaceae cluster, appeared to be more distinct from other family members.

Despite the worldwide economic impact of, and welfare issues associated with, infectious bovine abortifacients, as well as potential zoonotic threats to human health, accurate diagnosis of the causes of abortion is uncommon... Although Chlamydophila abortus is a known etiologic agent of ruminant abortion, several novel species of Chlamydia-like organisms have recently emerged as putative ruminant abortifacients... Serologic, bacteriologic, and histopathologic examination of fetal tissues identified no other infectious abortifacient agents in the Chlamydiales-positive samples... Sequence information was successfully obtained for 15 of these 22 samples with forward and reverse primers; sequences ranged from 140 bp to 194 bp (European Molecular Biology Laboratory/GenBank accession nos... GQ919016–GQ919030)... These 15 short sequences were carefully aligned to a representative set of 22 similar Chlamydiales 16S rDNA sequences, identified by a BLAST (www.ncbi.nlm.nih.gov/BLAST) similarity search of the European Molecular Biology Laboratory/GenBank database, plus alignment of an outgroup of 7 non-Chlamydiales sequences... Two of these sequence clusters represented 10 and 5 of the samples, whereas no samples were represented in the cluster containing the Chlamydiaceae, which includes C. abortus... Most (10/15) sequences were found in the cluster containing the Parachlamydiaceae... This finding agrees with those of the aborted bovine placenta studies in Switzerland and provides further evidence that Parachlamydia-like species may play a substantial role in bovine abortion in mainland Europe and the United Kingdom... Given the zoonotic potential and the economic and welfare impacts of bovine abortion on the agricultural sector, further studies are required to understand the incidence and pathogenic roles of these organisms in both humans and animals... These studies should include broader molecular epidemiologic studies, as well as detailed histologic/immunohistochemical investigations and organism recovery through culture of infected placental and fetal tissues.